Exemplary embodiments of the invention relate to a cylinder head device for an internal combustion engine and to an internal combustion engine having such a cylinder head device.
Cylinder head devices of this kind for internal combustion engines have long been known from the general prior art. The cylinder head device comprises a cylinder head having at least one first receiving region arranged on an inlet side of the cylinder head for at least one first camshaft to be mounted on the cylinder head. Further, the cylinder head has at least one second receiving region arranged on an outlet side of the cylinder head facing away from the inlet side for at least one second camshaft to be mounted on the cylinder head. Here, the camshafts serve to actuate gas exchange valves that control the inflow and outflow of gas into and out of corresponding combustion chambers, in particular cylinders, of the internal combustion engine.
The cylinders are formed, for example, by a crankcase of the internal combustion engine, which is designed as a reciprocating piston internal combustion engine, wherein the cylinder head can be connected or is connected to the crankcase.
Such a cylinder head device can be found disclosed in German patent document DE 10 2009 020 100 A1. Its cylinder head has a sealing surface, by means of which the cylinder head can be connected to a cylinder head cover. Further, the cylinder head has in each case sealing flange surfaces, by means of which an exhaust gas module and an intake module can be connected to the cylinder head. At the same time, it is provided that the sealing surface is integrated into the respective sealing flange surface.
It has been shown that, with conventional cylinder head devices, the supply of at least one element with lubricant can only be implemented very laboriously. To feed the lubricant, in particular lubricating oil, to the appropriate element to be supplied with lubricant, elaborate piping and a multiplicity of duct elements can be provided, which results in a high installation space requirement, a high weight and high costs of the cylinder head device.
An example of such an element to be supplied with lubricant can be a bearing point at which one of the camshafts is mounted. The element can also be a phase adjustment device, by means of which a phase adjustment of at least one of the camshafts relative to a crankshaft of the internal combustion engine can be carried out.
German patent document DE 10 2008 031 976 A1 disclose such a phase adjustment device in the form of a hydraulically actuatable phase adjustment device, which can be supplied and thereby actuated by the lubricant as the hydraulic fluid. The supply of such a phase adjustment device with lubricant has been shown to be particularly laborious. German patent document DE 697 07 213 T2 also discloses such a phase adjustment device that can only be supplied with lubricant as the hydraulic fluid very laboriously.
Furthermore, a cylinder head of an internal combustion engine having an actuator unit mounted in the cylinder head is disclosed in German patent document DE 10 2011 109 676 A1. The cylinder head has inlet channels and outlet channels. The inlet channels open out at an inlet flange surface and the outlet channels open out at an outlet flange surface. The outlet and inlet flange surfaces are angled with respect to one another such that their line of intersection lies above the cylinder head and the cylinder head therefore has a substantially triangular cross section. The actuator unit comprising at least one actuator is provided in an oil chamber of the cylinder head. The actuator controls and/or regulates the actuating unit for the gas exchange valves.
The element of the cylinder head device to be supplied with lubricant can also be at least one valve play compensation element, by means of which a valve play of at least one of the gas exchange valves can be compensated for. Conventionally, the supply of such a valve play compensation element with the lubricant as hydraulic fluid for actuating the valve play compensation element is very laborious.
Exemplary embodiments of the present invention are therefore directed to a cylinder head device for an internal combustion engine and an internal combustion engine having such a cylinder head device, with which a particularly easy supply of at least one element of the cylinder head device with lubricant can be realized.
In order to create a cylinder head device, in which at least one element can be supplied with lubricant, in particular lubricating oil, in a particularly easy manner, according to the invention, at least one intermediate wall of the cylinder head, by means of which the receiving regions are separated from one another at least in certain areas, is provided between the receiving regions at least in certain areas, wherein at least one duct element, by means of which at least one element of the cylinder head device can be supplied with lubricant, runs in the intermediate wall.
The lubricant can now be fed to the element to be supplied with lubricant via the duct element running in the intermediate wall with only a very low duct length, with only a very small number of parts and therefore particularly cost and weight effectively. In particular, it is possible in a particularly easy matter to divert lubricant from this duct element and, for example, to a first element of the cylinder head device to be supplied with lubricant which is arranged on sides of the first receiving region and to at least one second element of the cylinder head device to be supplied with lubricant which is arranged on sides of the second receiving region.
The duct element in the intermediate wall can therefore constitute a central distribution channel, by means of which the at least one element is to be supplied with lubricant in a simple manner. Further, it is possible to supply the duct element itself with lubricant, in particular lubricating oil, in a particularly easy manner. For this purpose, the duct element is connected, for example, to a lubricant circuit of the internal combustion engine so that the lubricant can easily flow into the duct element.
In a particularly advantageous embodiment of the invention, at least one transfer element formed separately from the cylinder head having at least one channel which is fluidically connected to the duct element, and by means of which the lubricant can be fed to the element, is provided. By means of the transfer element, lubricant can therefore be diverted from the duct element and to the element, i.e., transferred to the element, in a cost-effective and space-saving manner. As a result of this, a supply of the element or of a plurality of elements of the cylinder head to be supplied with lubricant, which particularly satisfies the requirements, is possible, as the lubricant can be diverted from the duct element and fed to the element at least substantially at any point on the duct element and therefore as required. As a result, it is also possible to supply the element with the lubricant with only a very short duct length. This enables the manufacturing effort and the costs of the cylinder head device to be kept low.
The duct element in the intermediate wall is produced, for example, by at least one hole and/or, when the cylinder head is cast, by means of at least one core element. The duct element can, however, also be produced in other ways.
It has been shown to be particularly advantageous when, at least in certain areas, the transfer element encompasses one of the camshafts mounted on the cylinder head, wherein the channel of the transfer element is fluidically connected to at least one second channel running in the camshaft, and wherein the lubricant can be fed to the element by means of the second channel. This enables the lubricant to be fed in a particularly space-saving manner. Further, the lubricant can be fed to the camshaft in the radial direction thereof or to its second channel in a particularly easy manner. Such a radial feeding of the lubricant keeps the axial installation space requirement of the cylinder head device low, as an elaborate axial feeding of the lubricant can be avoided.
In addition, this feeding of the lubricant to the camshaft and into its second channel enables the necessity for a sliding bearing of the camshaft, in order to feed the lubricant to the camshaft in the radial direction via the sliding bearing, to be avoided. Consequently, it is possible to mount the camshaft on the cylinder head by means of an anti-friction bearing mounting and therefore with particularly low friction. As a result, the friction of the cylinder head device and therefore of the internal combustion engine can be kept low, thus enabling the internal combustion engine to be operated with only a low fuel consumption and therefore with low CO2 emissions.
In a particularly advantageous embodiment of the invention, the element to be supplied with lubricant is in the form of a phase adjustment device, which is to be actuated by means of the lubricant and therefore hydraulically, and by means of which a phase adjustment of at least one of the camshafts can be effected in order to set control times of gas exchange valves. Conventionally, the supply of such a phase adjustment device with lubricant is particularly laborious, complex and cost intensive. With the cylinder head device according to the invention, the phase adjustment device can now be supplied in a particularly easy and space-saving manner.
At the same time, it is possible to feed the lubricant to the phase adjustment device via the duct element running in the intermediate wall from the inside, i.e., from a region in the transverse direction of the cylinder head device between the receiving regions, and not from the outside, thus enabling duct lengths for carrying the lubricant to be kept particularly short. As a result, a particularly low manufacturing and assembly effort can be realized for the cylinder head device.
In order to keep duct lengths for feeding the lubricant to the phase adjustment device particularly short, in a further embodiment of the invention, the phase adjustment device can be supplied via the second channel of the camshaft with the lubricant, by means of which the phase adjustment device can be actuated.
In a further, particularly advantageous embodiment of the invention, the element to be supplied with lubricant is in the form of a valve play compensation element, which can be actuated by means of the lubricant and therefore hydraulically, for compensating for a valve play of at least one gas exchange valve. Conventionally, the supply of such a valve play compensation element can also only be realized very laboriously with long duct lengths. With the cylinder head device according to the invention, this problem can be avoided by supplying the valve play compensation element via the duct element running in the intermediate wall.
A further embodiment of the invention, in which, at least in a sub-region, the duct element is in the form of a riser which has a first duct region and a second duct region that is adjacent to the first duct region and fluidically connected to the first duct region, has been shown to be particularly advantageous. Here, with reference to a flow direction of the lubricant, the first duct region extends through the riser (duct element) in the vertical direction of the cylinder head device from bottom to top. Further, the first duct region opens out into the second duct region. With reference to the flow direction of the lubricant, the second duct region extends in the vertical direction of the cylinder head from top to bottom. This embodiment of the duct element as a riser enables air to be removed from the lubricant flowing through the riser in a particularly advantageous manner. The lubricant flowing through the riser first flows upwards in the first duct region, then flows over into the second duct region and back down in the second duct region. When overflowing from the first into the second duct region, any air which is present in the lubricant can collect in an upper region of the riser, escape from the lubricant, and, for example, be discharged.
In a further, advantageous embodiment of the invention, at least one third duct region of the duct element, via which the lubricant can be fed to the valve play compensation element, branches off the second duct region. As the lubricant is fed to the third duct region via the second duct region, the second duct region can act as a collecting space in which a stored volume of lubricant collects, in particular when the internal combustion engine is deactivated. When the internal combustion engine is deactivated, lubricant can flow out of the second duct region, which acts as a collecting space, into the third duct region and further to the valve play compensation element so that the valve play compensation element cannot run empty of lubricant.
A particularly large collecting space for lubricant is provided by the second duct region when the third duct region is arranged in an end region of the second duct region. As a result, the part of the second duct region arranged above the third duct region in the vertical direction of the cylinder head device and of the internal combustion engine can be used as the collecting space. Here, it is particularly advantageous when the second duct region opens out into the third duct region. This enables a particularly large stored volume of lubricant to be realized.
The invention also includes an internal combustion engine for a motor vehicle, in particular a passenger car, having a cylinder head device according to the invention. The ability to supply the at least one element of the cylinder head device with lubricant via the duct element running in the intermediate wall enables the number of supply lines in the cylinder head device and/or in a control housing cover of the internal combustion engine to be kept particularly small. As a result, a particularly low installation space requirement, a particularly low weight and low costs of the internal combustion engine can be realized. Further, lubricant transfer points to the control housing cover as well as lubricant supply holes and lubricant transfer devices can be dispensed with, which benefits the low installation space requirement and the low costs.
Further advantages, characteristics and details of the invention can be seen from the following description of a preferred exemplary embodiment and with reference to the drawing. The characteristics and combinations of characteristics stated above in the description and the characteristics and combinations of characteristics stated below in the description of the figures and/or shown in the figures alone can be used not only in the specified combination in each case, but also in other combinations or in isolation without departing from the scope of the invention.